The invention relates, generally, to wide area networks (WANs) that consist of a number of local area networks (LANs) linked together to allow communication therebetween and, more particularly, to an improved method and apparatus for facilitating the exchange of administrative information between the LANs to minimize traffic due to administrative communications. The invention has particular applicability in minimizing the administrative traffic in a cellular telecommunications networks.
As will be appreciated, a LAN typically includes a number of processors linked together on a path such that they can communicate with one another. A WAN consists of a number of LANs communicating with one another over a network such as a public switched telephone network (PSTN), satellite transmission network or the like such that the LANs can communicate with one another to transfer information therebetween and/or function in a coordinated manner.
One common example of a WAN is a cellular telecommunications network. The typical cellular telecommunications network consists of a number of cell sites where each cell site includes a radio transmitter/receiver for communicating with mobile stations located in the cell served by that cell site. The cell sites are linked to one another and to a processor or processors on a path over which the cell sites and processor(s) can communicate with one another. The processor or processors in the cellular communications system include a call control for identifying mobile stations, assigning radio frequencies, routing calls and the like as will be understood by one skilled in the art. It will be appreciated that the typical cellular telecommunications network includes a number of these cellular communications systems serving different geographic areas. Each cellular communication system is linked to a switching system over voice trunks that transmit voice signals and a common channel signaling network that transmits call control signaling information. Each switching system includes linked processors that operate in coordination to route calls to and from the cellular communications systems, other switching systems and customer service lines. In such a telecommunications network it is considered that each of the cellular communications systems constitute a LAN as does each switching system and that these LANs form part of the cellular telecommunications network that constitutes the WAN.
In order for the LANs to properly communicate with one another, a directory of destinations or other administrative data is distributed to at least one processor in each of the LANs. If information in any of these processors is incorrect, the LANs will find it difficult or impossible to communicate with one another. Therefore, in existing WANs the administrative data in all of the LANs must be updated whenever the information in any LAN changes. It will be appreciated that in a telecommunications network, the traffic resulting from these updates is significant. Moreover, most WANs, in addition to the need for updating, perform regular audits of the entire WAN to ensure that all of the LANs are accounted for and properly communicating.
How often these updates and audits are transmitted over the WAN depends on the LAN protocols. Some protocols send out updates and/or audits every few minutes, others send out these messages every few seconds. While most WAN users never see these messages, this heavy flow of traffic over the WAN can cause link saturation and/or slow downs. Moreover, messages between LANs are typically transmitted over a connection oriented service such as a public switch telephone network (PSTN) where each administrative message is transmitted over a usage charged connection. As a result, the constant transmission of administrative messages not only uses valuable network resources but can also be expensive.
Thus, a problem exists in the art in that the existing updating and auditing systems for coordinating the communication of LANs in a WAN such as a telecommunications network increases network traffic, utilizes valuable network resources and is expensive.